The Construction of a MultiChAcc(MultireChargeable Accumulator)

Patrick Kudis, Ebbo Krahmer, Chenny Pelz, Isabel Rocholl

St. Raphael Gymnasium

Hi, everything's fine ?

Yeah, what about you ?

I forgot to cancel my date. The battery of my cell phone is empty! Could I use yours ?

Sorry, mine's empty too.

What should I do now ?

There is my flat. You can use our phone, you got the

number?

1 2

3

4

Yes, great, thanks ! ... I have an idea !

5 Tell me!We build an accumulator, which is rechargeable by my moves during sports. This accumulator could charge the cell phone.

6This would be very useful

Research topics

1. Little effort + green energy = enough energy to recharge a cell phone battery ?

2. Design of a suitable adapter for an intelligent network?

Structure

1. The forces of nature

1.1 Wind- & Water power

2. The forces of humans

2.1 The bicycle dynamo

2.2 The Lorentz force shaker

3. The MultiChAcc

4. Outlook

Wind and water wheel: Preliminarys

Wind and water wheel: Setup

Stand

Electric generator

Wind- and Waterwheel

Wind and water wheel: Measurements

Conclusion:The wheel does not produce enough energy to load the accumulator.

Speed in km/h

Voltagein V

Amperage in mA

Powerin mW

4 0.5 2 1

20 1.5 4 6

Bicycle dynamo: Setup

Manual generator

Flank dynamo mounted on a bicycle

Bicycle dynamo: Measurements

Factors for a high energy level:

1. Frequency

2. Efficiency of the dynamo

Conclusion: Is the frequency high enough we produce enough power to charge the accumulator directly.

FrequencyIn Hz

Voltagein V

Amperage in A

Powerin W

1.5 3.0 0.6 1.8

2.2 3.8 1.0 3.8

Lorentz force shaker: Preliminarys

Induction coil

Magnet

Spring

SpringDiode

Cable

Lorentz force shaker: Setup

Induced voltage depends on:

1. Shaking rate

2. Number of turns in the coil (we used 20000)

3. Magnetic field strength.

Induction coil Tube with magnet

Lorentz force shaker: Measurements

Conclusion: The induced voltage is sufficient to charge the MultiChAcc.

Shaking frequency

in Hz

Peak voltage

in V

Peak amperage

in mA

Peak power

in mW

5 19.7 0.9 19

10 35.1 1.75 62

14 41.2 2.1 87

MultiChAcc: Setup

Accumulator

- 17 Wh- Output voltage:

3.7 V-4.2 V- Input voltage:

from 3.7 V

MultiChAcc input

MultiChAcc: Setup

USB inputUSB output

- Rectifier

MultiChAcc: Setup

- Rectifier

- DC step up booster

MultiChAcc: Setup

MultiChAcc: Setup

- Rectifier

- DC step up booster

- Voltmeter and switch

MultiChAcc: Setup

- Rectifier

- DC step up booster

- Voltmeter and switch

- Diode

MultiChAcc: Setup

InsideOutside

- in series- 6 V to 14 V, 20 mA

MultiChAcc: Gadgets

USB port

NFC tags